The spacer I used I got at a swap meet--it was a Mr.Gasket POS--I agree with the other post about making your own out of metal--I searched at home depot,and they have a wide variety of ductwork adaptors that come real close,but not a perfect fit--PVC pipe comes close too,but again,not a perfect tight seal--The people who work there must have thought I was nuts,walking around with a plastic carb spacer and comparing it to anything in the store thar looked like it would work!--I even tried the courragated PVC drain pipe stuff,it fit the best but the "threads" on it make it unsuitable because they spiral upwards,you cant cut it and get a uniform I.D.--You guys will laugh,but the cast iron ring a toilet sits on fit real close--and its got lots of holes you could bolt it to the airleaner with!--they make it in PVC too. /forums/images/graemlins/rotfl.gif
The regular adaptor can be had at any speed shop,but I have no luck with them,must be the climate makes them brittle or something.I had a few factory spacers that were mentioned,but a quadrajet is not the same size as my AFB carb air horn--the edelbrock is about the same as the quadrajet,a hair smaller--the AFB I have is nearly a 1/2 inch smaller than a quadrajet.So far the duct work adapter is the best I can come up with--I'll just grind out the two rivets and close it up a little more and braze it together--at 3.99 its a lot sturdier than plastic,and cheaper too!.